Telephone metering system.



No. 672,546. Patented Apr. 23, I901.

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TELEPHONE METE BING SYSTEM.

(Applicatidn filed Nov. 27. 1899.=

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omajafiajgdsa PM Jj @%W No. 672,546. Patented Apr. 23, l90l. D. M. BLISS.

. TELEPHONE METERING SYSTEM.

(Application filed Nov. 27, 1899.;

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UNITED STATES PATENT OFFICE.

DONALD M. BLISS, OF LOWELL, MASSACHUSETTS, ASSIGNOR TO THE AUTO- MATIC TELEPHONE METER COMPANY, OF NElV JERSEY.

TELEPHONE METERING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 672,546, dated April 23, 1901.

Application filed November 2'7, 1899- Serial No. 73$,L'7O (No model.)

To all whom it may concern: of which ais the driving-wheel, adapted to be Be it known that I, DONALD M. BLISS, of actuated by means of a pawl 5 carried by a Lowell, county of Middlesex, and State of vibrating armature b, the said pawl being Massachusetts, have invented an Improveadapted to cooperate with ratchet-teeth on 55 5 mentin Telephone h/leteringSystems,of which the said wheel a. The said armature b is arthe following description, in connection with ranged to be acted upon by an electromagnet the accompanyingdrawings,isaspecification, 0, adapted to be connect-ed by a circuit like letters on the drawings representing like with the line-wires l 2 of the main telephonep rts. circuit, so that when the telephone is in use 1o Thepresentinvention relates toatelephone and the pulsating current in operation the metering system and is mainly embodied in a said pulsating current will pass over the main novel method of measuring or recording teleline 1 2 through the coils of the magnet 0, phone usage automatically, the said method causing the armature b, which is polarized, consisting in superimposing upon the line a to vibrate and rotate the wheel a. The source 15 slow pulsating or alternating current while of pulsating current, which may be of any the telephones are in use, the said current suitable nature, such as a slowly-traveling serving to operate a suitable recording inalternator, is indicated at A, Fig. 2, and is strument, but being incapable of affecting shown as connected in series with the opera the telephone instrument, so that it will not tors plugs B and C, so that when connection 2o interfere with the ordinary use thereof. between two subscribers is made at the cen- Figure 1 is mainly a diagram View, with tral office the inaudible current will pass over parts shown in section and parts in elevation, the line to operate the meter, as above deof a telephone, including a recording instruscribed. ment capable of operating in accordance with As thus far described, it is obvious that 25 this invention. Fig. 2 is a diagram of the each meter might be continually connected. connecting-plugs employed at the central ofwith the main-line circuit, so as to record the fice, the operators set, the calling-generator, length of time each instrument is used when and other parts which have no connection two instruments are connected together at with the present invention being omitted; the central olfice, or, if desired,arecord might 0 and Fig. 3 is a modification of the recording be kept of each time a telephone was used, instrument, which will be hereinafter deeven to communicate with the operator at scribed. the central oflice. It is at present customary, In carrying out the invention each telehowever, to charge telephone service only to phone is provided with a recording instruthe calling subscriberin other words, to 5 mentwhich may be of any suitable or usual charge each subscriber for the number of kind arranged to be electrically operated in times he has called for and obtained a talkresponse to the action of a pulsating or altering connection with another subscriber. T0 nating current, and while two telephones are this end a further feature of the present inin use the said pulsating current is superimvention consists in the construction and ar- 0 4) posed on the line, so as to operate one or both rangement of certain devices for causing the recording instruments then in circuit, it bemeter-actuating current to be placed in ciring usually desirable, however, to have only cuit with one only of the recording instruone of the saidinstruments operated, so that mentsviz., the instrument at the telephone only the calling subscriber may have the call of the subscriber who has first called central 5 43 recorded. office.

The method embodying the invention will As shown in Fig. 1, the circuit 10 20 is norbe more readily understood in connection mally broken and adapted to be closed at the with a description of the apparatus herein contacts d (1 one of the said contacts being shown,which com prises, essentially, a recordformed on a movable member or arm (i piv- I00 50 ing instrument at each telephone, indicated oted at (Z and arranged to be moved toward in Fig. 1 as a train of wheels a, a a and a the other contact in response to the operation of the magneto 72;. As herein shown, the said arm d is arranged to be moved in the proper direction to carry the contact cl toward the contact d by means of a plunger cin the cylinder 6 which communicates, by means of a duct with a pump-plunger g in a pumpcylinder g. The said pump-plunger g as shown, is connected, by means of an arm g with a gear-wheel g, meshing with the wheel h, which is rotated by the actuating-handle for the magneto b When, therefore, a subscriber calls central office, the pump-plunger will be actuated, causing compressed air to pass through the duct f into the cylinder (2 driving the plunger 6 outward and moving the arm (1 until the contact 01 engages the contact d thus closing the meter-actuating circuit. The meter at the telephone of the calling subscriber is thus placed in opera tive condition ready to respond to the action of the pulsating current when connection has been made at the central office, the meter at the telephone of the called subscriber, however, being inoperative, because the said called subscriber has not used his magneto. Since the magneto is only momentarily used, however, it is necessary to provide the device with means for maintaining the meter-circuit closed after the operation of the magneto has ceased. This may be accomplished, as herein shown, by utilizing the local-battery cur rent of the telephone, the circuit of which is controlled by the gravity-hook and only closed when the receiver is in use.

As herein shown, the arm 61 is arranged to constitute the armature of an electromagnet 7a, which is connected by conductors and k with the local battery M, the circuit of which is controlled in the usual way by the gravityhook 70". As soon, therefore, as the receiver is removed from the gravity-hook, as it naturally is as soon as the magneto has been operated, the circuit 7c -and 70 will be closed and the magnet 70 will become energized, attracting the arm 61 and preventing the same from moving, so as to separate the contacts (1 and (1 So long, therefore, as the telephone is in use the meter-actuating circuit will be closed and the meter operated in response to the action of the pulsating current. The arm d is normally out of the magnetic field of the magnets 70, so that unless it is initially moved in response to the operation of the magneto it will not be attracted by the said magnet is, the operation of the meter depending, therefore, upon the initial operation of the magneto.

The ductf is controlled by a loosely-seated ball-valve f which permits the air to leak out of the cylinder 6 after a short interval of time, so that as soon as the conversation is completed and the receiver hung up, thus breaking the circuit through the magnet 7a, the arm d will return to its normal position, the plunger e having receded.

As herein shown, a spring e is interposed between the arm d and the plunger e, so that ing, therefore, a certain amount of reserve force to hold the said contacts together, or at least to keep the arm (Z in the magnetic field of the magnet 70 during the interval which may elapse between the operation of the magneto and the removal of the receiver from the gravity-hook. It is also desirable that the movement of the arm (Z away from the magnets 7c should be retarded, even after the pump-plunger c has settled back to its normal position, for the reason that the person using the telephone may move the gravityhook accident-ally or otherwise, thereby temporarily breaking the local-battery circuit. For this reason the arm (Z is also shown as arranged to be influenced by the plunger (Z of a dash-pot (Z the stem of said plunger being shown as provided with a shoulder d enthe arm d Since the dash-pot plunger, if actually connected with the arm (1", would unduly retard the upward movement of said arm, which should be as prompt as possible, the spring (1 is shown as interposed between said arm and the shoulder (Z on the plunger-stem, the said spring yielding in the first upward movement of the plunger-stem and permitting the contacts 61 and (Z to come together promptly, the plunger following as the spring exercises its influence.

As shown in Fig. 1, the meter or recording device is arranged to operate continuously during conversation, so as to record the actual length of time during which the telephone is in use. It is, however, immaterial what kind of a recording device is used, and in practice a device to record merely the numberof calls would probably be employed. The essential parts of a recording device arranged for the latter purpose are shown in Fig. 3, the actuating-wheelct being operated by a vibrating armature and pawl, as before, but being additionally controlled in its movement by a stop a, arranged to permit the wheel a, to move only a predetermined distance at each operation. As herein shown, the said stop a is formed on an arm (L pivotally supported at a and having a slot 0. and spring a to permit a certain amount of 1011 gitudinal movement when the stop a is in contact with one of a number of equallyspaced stops or pins 61,", carried by the wheel a The arm a is normally positioned, as shown, so that the stop 0& is out of the path of the pins a", and the said arm is connected, as by a link a, with the contact-arm 61 so that when the said contact-arm is moved in response to the operation of the magneto, as hereinbefore described, the stop a will be moved into the path of one of the pins a". As soon as connection is made at the central office the vibrating armature will begin to operate, as before, and to rotate the wheel a until one of the stops at" comes in contact with the stop 60 the spring a then yielding IIO and permitting a longitudinal movement of the arm at until the pivot a is engaged by the end of the slot 61/ The Wheel will then be stopped, this amount of movement serving to move the recording device one step in any suitable or usual way. The current impulses in the magnet-coils will not produce any further movement of the wheel a since the stops will resist the pull of the magnet and prevent the vibrations of the armature. As soon as the subscriber finishes using his telephone, however, the arm (1 will fall back to its normal position, as before, disengaging the stops, after which the spring at will act to produce a longitudinal movement of the arm 0, so that the next time the arm 01 is moved the stop 0, will come up behind the pin with which it was last in engagement,-

ready to be engaged by the next pin to stop the wheel after the desired movement.

I do not herein claim, broadly, the means for controlling the operation of the meter at the telephone or the relation of said meter to the call-signaling device, my invention, so far as relates to this part of the apparatus, residing only in the specific construction and arrangement of the apparatus shown and described. The operation of the meter by an inaudible current, however, I believe to be broadly new, and in this respect I do not intend to limit the invention to the specific arrangement of instrumentalities herein shown as capable of effectually carrying out the invention.

I claim- 1. That improvement in the art or method of measuring or recording telephone usage which consists in superimposing on the line an inaudible pulsating or alternating current adapted to operate a recording instrument while conversation is being carried on.

2. That improvement in the art or method of measuring or recording telephone usage which consists in superimposing on the line when two telephones are connected, for the purpose of communication, an inaudile pulsating or alternating current adapted to operate a recording instrument.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

DONALD M. BLISS.

Witnesses:

LAWRENCE BOND, J As. J. MALoNEY. 

